Machine for machining curved stereotype printing plates



May 13, 1924.

T. R. G. PARKER MACHINE FOR MACHINING CURVED STEREOTYPE PRINTING PLATES Filed Oct. 28, 1922 6 u w W 6 mm 91 W 6? K 7 i I I Patented May 13, 1924.

UNITED STATES PATENT OFFICE.

THOMAS ROBERT GILLETT PARKER, OF ALTRINGHAM, ENGLAND, ASSIGNOB T0 LIND- TYPE AND MACHINERY LIMITED, 01? LONDON, ENGLAND, A COMPANY.

MACHINE FOR MACHINING CURVED STEREOTYPE PRINTING PLATES.

Application filed October 28, 1922. Serial No. 597,495.

T all whom it may concern:

Be it known that I, THOMAS ROBERT GIL- LETT PARKER, a British subject, and resident of Altrincham, in the county of Chester, England, have invented new and useful Improvements in or Relating to Machines for Machining Curved Stereotype Printin Plates, of which the following is a specification.

This invention relates to machines for machining curved stereotype printing plates of the construction set forth in the specification of Letters Patent No. 1,233,698, in which the said plates are conveyed through the mar chine by pivoted fingers reciprocated longitudinally of the machine, and automatically turned into and out of plate-engaging position respectively, during their active and idle strokes.

According to the said Letters Patent, the turning of a finger into plate-engaging position is effected by the engagement of that finger with a block which, when a plate is inaccurately located, is prevented from moving into its operative position. The object of the invention is to provide an improved and simplified construction of these devices, wherein the finger is turned into plate engaging position by engagement with a block which, when a plate is inaccurately located, is moved out of its operative position.

The invention will be described with reference to the accompanying drawings, in which Figures 1 and 2 are respectively a side elevation and a plan showing the pertinent parts at one side of the plate-receiving end of a machine of the above named construction, 1 being the respective side frame, 2 a traverser bar reciprocated by means of a rack 3 and gearing (not shown), 4 a plate-traversing finger pivoted in a recess 5 in the traverser bar, 6 the plate-receiving table, and 7 a plate correctly located on the runway in position to be engaged by the finger 4 and its companion finger carried by the traverser bar on the opposite side of the machine.

According to the constructional form of the invention illustrated, there is provided for each of the runways leading to the shaving arch, that is to say, at each side of the machine, a trip lever 8 having a projection 9 aligned with the respective runway, and

" in such position that when a plate is placed on the runway in incorrect position relatively to the shaving arch, its rear end will overlap the projection 9, and hold the trip lever 8 depressed, thereby preventing the finger 4 from being turned into plate-engaging position.

This result may conveniently be attained by securing each trip lever 8 to a short honzontal shaft 10 extending through the side frame 1 and having fixed on its outer end, a lever arm 11 carrying a block 12 which, when in its higher position, serves for swinging the finger 4 on its pivots during the return or idle strokes of said finger. The lever arm 11 with the block 12 thereon is normally retained in its raised position by a spring 13, acting between a depending part 14 of the arm 11 and the side frame, a stop 15 being provided for limiting the movement under the influence of the spring.

In the drawings the parts are shown in normal position, with a plate 7 correctly located against the projection 9, the traverser bar in a position occupied by it shortly after the commencement of its operative stroke, and the finger 4 extended ready to engage and move forward the plate 7, it being noted that the end of the finger 4 is recessed or undercut asindicatedby the dotted line 16 to enable it to pass over the projection 9.

lVhen, with the foregoing arrangement, the rear end of a plate overlaps, as aforesaid, the trip lever projection 9, the latter,

and consequently also the finger-turning the end of its return stroke with the finger 4 in inoperative position within the recess 5, the said block cannot contact with the extension 17 of the finger 4, which is then projectingto the outside of thetraverser bar, and the finger 4 remains in its inoperative position. YVhen, on the contrary, a plate is presented in proper position relatively to the shaving arch, the rear edge of such plate just clears the trip-lever projection 9, as shown in the drawings, and consequently the spring 13 holds the fingerturning block 12 in operative position, with the result that when the finger 4 is moved past it on the return stroke of the traverser bar, the said finger is swung into its plateengaging position, so that during the next feeding movement of the traverser bar the finger engages the plate, and, acting in conjunction with the companion finger on the traverser bar, at the opposite side of the machine, which it will be understood is controlled by similar means, propels the plate into the shaving arch.

It will thus be seen that, with the beforedescribed means, unless the fingers clear the rear edge of the plate during their idle stroke, they cannot be turned into operative position, and consequently they cannot engage with any part other than, as they should do, the said rear edge.

Having described my invention, I declare that What I claim and desire to secure by Letters Patent is 1. In a machine for machining curved stereotype printing plates, the combination with a reciprocable plate-traversing finger and a block adapted to engage said finger during its reciprocation and cause it to move into plate-engaging position, of means whereby said block is moved out of its operative position by an inaccurately located plate.

2. In a machine for machining curved stereotype printing plates, the combination with a reciprocable plate-traversing finger and a block adapted to engage said finger during its reciprocation and cause it to move into plate-engaging position, of a trip lever operatively fast to the relatively fixed block and adapted to move the latter out of operative position when engaged by an inaccurately located plate.

3. In a machine for machining curved stereotype printing plates, the combination with a reciprocable plate-traversing finger and a block adapted to engage said finger during its reciprocation and cause it to move into plate-engaging position, of a trip lever adapted to be engaged by an inaccurately located'plate, a lever-arm secured to the said block and a rock shaft common to said lever arm and the trip lever.

4. In a machine for machining curved stereotype printing plates, the combination with a reciprocable plate-traversing finger and a block adapted to engage said finger during its reciprocation and cause it to move into plate-engaging position, of a trip lever aligned with the runway for the plates and adapted to be depressed by an inaccurately positioned plate, a lever arm integral ee mes with said block and a rock shaft common to both the said lever arm and the trip lever.

In a machine for machining curved stereotype printing plates, the combination with a reciprocable traverser bar and a platetraversing finger carried by said bar, of a rock shaft mounted in a stationary bearin two levers fast to the rock shaft, a projection on one of the levers aligned with the runway for the plates, and a block secured to the other of the levers adapted to engage the plate-traversing finger during the rcciprocaion of the traverser bar and cause said finger to move into plate-engaging position.

6. In a machine for machining curved stereotype printing plates, the combination of a reciprocable traverser bar, a recess in said bar, a plate-traversing finger pivoted in the recess, a projection on the finger adapted to protrude from the recess when the finger is in. inoperative position, a rock shaft mounted in a stationary bearing, two levers fast to the rock shaft, a projection on one of the levers normally aligned with the runway tor the plates and adapted to be depressed by an inaccurately located plate, a block secured to the other of the levers and normally located in the path of the projection on the plate-traversing finger, and means adapted to yieldingly retain both levers in normal position.

7. In a machine for machining curved stereotype printing plates, the combination of a reciprocable traverser bar, a recess in said bar, a plate-traversing finger pivoted in the recess, a projection on the finger adapted to protrude from the recess when the finger is in inoperative position, a rock shaft mounted in a stationary bearing, two

levers fast to the rock shaft, a projection on one of the levers normally aligned with the runway for the plates and adapted to be depressed by an inaccurately located plate, a block secured to the other of the levers and normally located in the path of the projection on the plate-traversing finger, a spring tending to hold the levers constantly in normal position and a stop for limiting the movement of the levers under the influence of the spring.

In testimony whereof I have afiixed my signature hereto.

THOMAS ROBERT GILLETT PARKER. 

